JP2007536513A - Component inspection apparatus and inspection method based on structurally adjusted vibration characteristics - Google Patents

Abstract

A component inspection apparatus based on a structurally adjusted vibration characteristic capable of detecting a defect in a component of an assembly prior to the component being mounted in the assembly.
A part inspection apparatus operates a part to be tested at a speed different from that at which the part operates during normal use in an assembly and under different loads. In order to compensate for this difference in speed and load, the component inspection device is structurally structured so that there is a relationship between the mode frequency and operating speed of the component inspection device and the mode frequency and operating speed of the assembly. Adjusted.

Description

  The present invention relates to an inspection apparatus and an inspection method for detecting an abnormality of a component in an assembly before the component is mounted in the assembly, and more particularly, depending on the structure of the assembly or the inspection device. This relates to detecting abnormalities in the internal components based on the vibration characteristics that can be adjusted.

  As the importance of riding in quiet cars increases, the level of noise, vibration and harshness (NVH) in the vehicle's powertrain will help define the overall noise level of the vehicle. It has come to be regarded as having an important role. For example, gear noise can be a major cause of unacceptable transmission NVH levels, in other words, unacceptable NVH levels in vehicles. To address these issues, various gear measurement and inspection devices have been developed to identify and remove noisy gears before they are incorporated into the transmission.

  Current schemes also include placing a test bench in the transmission manufacturing plant to inspect NVH levels after the transmission is assembled. Computer simulations are also used for the performance of transmissions and finished vehicles. This is complemented by field performance tests of manufactured and assembled transmissions.

  Testing after transmission assembly reduces the number of transmissions installed in the vehicle that generate noise, but detecting an unacceptable NVH level in a line end test bench or on-site performance test Expensive and wasteful. Therefore, it is desirable to perform different weighing / inspection methods in the machining department for detection of gear defects before assembly. However, current scales in place in the machining department have limited detection capabilities and often cannot detect minor gear anomalies that can cause unacceptable NVH levels in vehicles.

  Gear metering devices currently available in the machining sector measure gear dimensional characteristics and tooth surface shape. They cannot perform a functionality based NVH checking of the gear before the gear is used in the transmission assembly. In addition, there are several other types of weighing equipment in place, including transmission error (TE) test equipment and test equipment that measures vibration characteristics, but these are also limited in capacity. .

  One of the limitations of these devices is that the dynamic response of those structures does not show any correlation with the response of a fully assembled transmission. Therefore, they cannot detect slight micro-level defects that would generate noise in the assembled transmission. In such a device, the structural parts are thus very hard and the excitation level due to gear failure is low. Thus, due to the low vibration level of the gear inspection device structure, this structure is no longer similar to the finished assembly, and the test results are shown when the tested parts are installed. It may not represent how it works.

  Accordingly, there is a need for a component inspection apparatus and inspection method that can detect minor defects in the components of an assembly prior to the component being installed in the assembly.

  The present invention provides a component inspection apparatus and inspection method capable of detecting slight defects in components of an assembly before the components are mounted in the assembly.

  The present invention provides a method for detecting defects in a part in an assembly prior to the part being installed in the assembly. The parts are movable at one or more speeds in the assembly. The method of the present invention includes configuring a component inspection apparatus for operating a component at one or more predetermined speeds. The inspection device includes at least one sensor. The operating speed of the parts in the inspection device is selected and determined from one or more predetermined speeds. At least one abnormal frequency of a component in the inspection device is determined as a function of its operating speed. At least a part of the inspection apparatus is configured to have at least one mode frequency within a predetermined frequency band. The predetermined frequency band of the inspection apparatus includes at least one abnormal frequency of components in the inspection apparatus. At least a part of the inspection apparatus has a mode characteristic such that a parameter value for identifying a component abnormality in the inspection device falls within a predetermined range with respect to a component abnormality identification parameter value in the assembly. Configured as follows. The abnormality identification parameter of the component in the inspection apparatus is a deviation between the amplitude response of the inspection apparatus using the component having at least one abnormality and the amplitude response of the inspection apparatus using the component having substantially no abnormality. Is defined as The mode characteristics and amplitude response of the inspection device are determined using at least one sensor. The part operates in the inspection apparatus, and the value of a predetermined response parameter of the inspection apparatus is measured while the part is operating in the inspection apparatus. This facilitates detection of abnormalities in the part.

  The present invention provides a method for detecting an abnormality in a particular gear of a vehicle transmission prior to the gear being installed in the transmission. The method includes determining at least one mode frequency of the transmission using at least one sensor on the transmission housing. The gear mesh frequency of the transmission is defined as a function of the number of teeth of a particular gear and the rotational speed in the transmission. It is determined whether the meshing frequency of the transmission gear is within a predetermined transmission vibration band. The predetermined transmission frequency includes at least one of the mode frequencies of the transmission. The positional relationship of the transmission gear meshing frequency with respect to at least one of the transmission mode frequencies is also determined. Further, it is determined whether at least one of the harmonic frequencies of the transmission gear meshing frequency is within a predetermined transmission frequency band. The positional relationship of at least one harmonic frequency of the transmission gear meshing frequency is also determined with respect to at least one mode frequency of the transmission. At least one sensor on the transmission housing is used to determine an amplitude response (first amplitude response) of the transmission in a state including a gear having at least one abnormality. At least one sensor on the transmission housing is used to determine an amplitude response (second amplitude response) of the transmission in a state including a gear having substantially no abnormality. An anomaly identification parameter for a particular gear in the transmission is determined. This identification parameter is defined as the deviation between the first amplitude response and the second amplitude response. A gear inspection device is configured and includes at least one inspection device sensor. The inspection device can rotate a specific gear at one or more predetermined speeds. The rotational speed of a specific gear in the inspection device is selected and determined from one or more predetermined speeds. The rotational speed of the specific gear in the inspection device is different from the speed used to determine the meshing frequency of the transmission gear. The inspection device gear meshing frequency is defined as a function of the number of teeth of a specific gear and the rotational speed in the inspection device. At least one of the harmonic frequencies of the inspection device gear meshing frequency is determined. At least a part of the inspection apparatus is configured to have at least one mode frequency in a predetermined frequency band. The predetermined frequency band of the inspection device includes at least one of the inspection device gear meshing frequency and the harmonic frequency of the inspection device gear meshing frequency. At least a part of the inspection device is configured to have a mode characteristic such that the value of the abnormality identification parameter of a specific gear in the inspection device is within a predetermined range based on the value of the abnormality identification parameter of a component in the transmission. Is done. The abnormality identification parameter of a specific gear in the inspection device includes the amplitude response of the inspection device using a gear having at least one abnormality and the amplitude response of the inspection device using a gear having substantially no abnormality. Is defined as the deviation between. The mode characteristics and amplitude response of the inspection device are determined using at least one sensor. A specific gear in the inspection apparatus is rotated, and a value of a predetermined response parameter of the inspection apparatus is measured. This facilitates detection of anomalies within a particular gear.

  The present invention also provides an inspection device based on structurally tuned vibration characteristics for detecting anomalies in moving parts in an assembly prior to its being installed in the assembly. . The assembly has a mode frequency, and the part has at least one assembly abnormal frequency that is a function of the operating speed of the parts in the assembly in which an abnormality in the part is detectable. At least one of the abnormal assembly frequencies is within a predetermined frequency band of the assembly. The inspection device includes a first actuator that can operate the component at one or more predetermined speeds. The component has at least one inspection device anomalous frequency that is a function of the operating speed of the component in the inspection device. At least one of the inspection apparatus abnormal frequencies is different from the at least one assembly abnormal frequency. The structure supports the part while the part is actuated by the first actuator. The structure is configured such that at least a part of the inspection apparatus has at least one mode frequency within a predetermined frequency band of the inspection apparatus. The predetermined frequency band of the inspection device includes at least one of the inspection device abnormal frequencies. The sensor measures the value of the predetermined response parameter of the inspection device while the first actuator is actuating the part.

  FIG. 1 shows a component inspection apparatus, specifically, a gear inspection apparatus 10 according to the present invention. As will be described in detail later, the inspection device 10 detects abnormalities in a specific part, in this embodiment, the gear 12, based on structurally adjusted vibration characteristics. It is an inspection device for detecting prior to being attached to a solid body. The inspection device 10 includes a first actuator, which in this embodiment is an electric motor 14, capable of rotating the gear 12 at one or more predetermined speeds. The motor 14 rotates the pulley 16 and similarly rotates the belt 18 that transmits the rotational movement of the pulley 16 to the second pulley 20.

  The inspection apparatus 10 also includes a structure of the type of column 21 that includes a spindle with rotating parts and an expandable collet for supporting the gear 12. Specifically, the gear 12 is supported along the direction of the axis of rotation by a spindle (hereinafter denoted by reference numeral 21 for the sake of convenience) and an over-arm 23. Pulley 20 rotates a portion of the spindle, thereby rotating gear 12.

  A master gear 24 (second part, meshing gear) is arranged to mesh with the gear 12 and is driven by the gear 12 when the gear 12 is rotated by the motor 14. The master gear 24 is placed on the second spindle 26. The second spindle 26 is mounted on a guide portion 28, which is mounted on a plurality of precise guide paths 30 that are visible only one in FIG. The guide part 28, the guide path 30, and the spindles 21, 26 are all provided on the base part 31. The inspection device 10 is placed on a rubber separation plate 32 in order to remove vibration transmitted from other vibration sources.

  By moving the guide portion 28 on the guide path 30, it is possible to change the manner and amount of contact between the gear 12 and the parent gear 24. For example, when the guide portion 28 is sufficiently close to the spindle 21, the gear 12 and the master gear 24 are in a double side contact state, in other words, a tooth on one gear is simultaneously with an adjacent tooth on the other gear. Engage in contact. Therefore, the other gear simultaneously contacts both side surfaces of the teeth on one gear. As the guide 28 moves away from the spindle 21, the gear 12.24 can be engaged in a single side contact. Further, moving the guide portion 28 closer or further away from the spindle 21 provides a means for adjusting the size of the backlash, ie, the gap between the two gears 12, 24.

  As will be described in detail later, it may be preferable to provide a specific backlash when inspecting the gear 12. An adjustable stop 33 adjusts the engagement between the master gear 24 and the gear 12 to be inspected at a preset amount of spacing or backlash. In the engaged position, the guide portion 28 is fixed in place so that the backlash is constant throughout the test.

  Another actuator, a DC servo motor 34, is provided to apply a torque load to the gear 12 when the motor 14 operates the gear 12. Of course, other types of actuators can be used, such as magnetic particle brakes, hydraulic motors or any dynamic braking mechanism. Motor 34 provides a dynamic torque load to drive sprocket 35, which in turn applies torque to second drive sprocket 36 (pulley) via belt 38. A sprocket 36 is attached to the spindle 26 at a position below the master gear 24, thereby applying a torque load to the master gear 24. Accordingly, the master gear 24 cooperates with the gear 12 and the motor 34 so that the motor 34 applies an appropriate torque load to the gear 12 via the master gear 24 in the single side engagement state. This aids in simulating actual operating conditions such that the gear 12 is operating in the transmission under a torque load due to single side engagement.

  When the gear 12 rotated by the motor 14 drives the parent gear 24 under a torque load for a predetermined period, the vibration sensor 40 disposed on the upper arm 23 and the parent gear spindle 26 on the housing The arranged vibration sensor 41 measures the value of a response parameter such as acceleration, and outputs this information to an output device such as a computer 42. In this embodiment, the sensors 40, 41 are accelerometers, but other forms of sensors can also be used. For example, acoustic sensors or microphones can be used to measure sounds and output their magnitude to a computer such as computer 42. Similarly, speed sensors or displacement sensors can also be used. Sensors such as vibration sensors 40, 41 must have sufficient bandwidth to measure parameters over the desired frequency band of interest. The inspection device 10 also allows an operator to adjust various components of the inspection device 10 and allows data or other response parameters to be entered in both manual and automatic modes. Includes a touch screen 44. Other types of worker interfaces may also be utilized.

  As described above, the vibration characteristics of the inspection apparatus 10 are structurally adjusted, and are configured to detect a failure of a component such as the gear 12. “Structurally adjusted” means that at least a part of the inspection device 10 is configured such that at least one mode frequency of the inspection device 10 is included in a predetermined frequency band. As will be described later, the predetermined frequency band of the inspection apparatus 10 can be determined using a specific rotation speed of the inspection gear and an abnormal frequency of the gear.

  The mode frequency selected for the inspection device 10 is typically not the same as the mode frequency of the transmission or other assembly into which the gear 12 or other component to be tested is mounted. This is because the gear 12 is operated in the inspection apparatus 10 at a lower speed than when operating in the transmission. This is necessary to avoid damaging the test gear in the inspection device 10 that operates the gear under dry conditions, which is different from the actual transmission assembly.

  The inspection device 10 is configured to detect an abnormality of the gear 12. For example, cuts, grinding streaks, and “plus-tip” conditions are all abnormalities that can occur in gears. Such abnormalities were often not detected when using conventional measurement devices, such as inspection devices based on vibrations, before the gears were installed and operated in the transmission. When these anomalies are not detected before the transmission is installed in the vehicle, they can generate undesirable noise and vibration when the vehicle is driven. Furthermore, if gear abnormalities are detected after assembly, i.e. in the transmission assembled at the end of the line, there is a significant cost penalty due to wasted labor costs and a significant number of parts are scrapped. Can be.

  In order to detect other gear anomalies that may produce undesirable NVH characteristics in the vehicle, including these anomalies, the inspection device 10 is correlated with the assembled transmission anomalies at the end-of-line test bench. Structurally adjusted to have anomaly detection capability. This general concept is shown schematically in FIG. In FIG. 6 (b), the excitation generated by a gear such as gear 12 in an assembly such as transmission 46 is expressed as a function of gear speed (speed 2) and gear tooth geometry. Is done. The transmission 46 operates under a torque load (Load 2) and receives structural excitation due to gear tooth geometry and gear anomalies.

  Thereafter, the response of the transmission, specifically the vibration response, is measured. FIG. 2 (a) shows that an inspection device, such as inspection device 10, can be structured to respond to gear tooth abnormalities in a manner that is correlated with transmission 46 abnormality. Even in the inspection device 10, the excitation is expressed as a function of the gear speed (speed 1) and the gear tooth geometry. A torque load (load 1) can be applied to the gear inspection device and the vibration response of the inspection device 10 is measured.

  As shown in FIG. 2, the rotational speed of the analyzed gear differs between the inspection device 10 (speed 1) and the assembled transmission (speed 2). Furthermore, the applied torque load is different between the two. However, the gear teeth geometry is the same. Therefore, the inspection apparatus 10 is not configured to have the same mode frequency and response characteristics as the assembled transmission 46. Rather, the inspection apparatus 10 is configured to have a mode frequency and response characteristics that provide a vibration response similar to the vibration response in the transmission 46, taking into account the difference in operating speed between the two structures.

  FIG. 3 represents a flowchart 48 illustrating the method of the present invention. First, in this flowchart 48, a plurality of steps are shown in order, but two or more steps may be executed simultaneously, or may be executed in a different order from that shown in the figure. Note that this may be the case. First, in step 50, the fundamental frequency of the assembly, such as transmission 46, and the mode frequency over the band of interest for mode analysis are determined. The band of interest is a predetermined frequency band of the transmission that is selected based at least in part on known operating conditions of the transmission. Of course, if only one mode frequency is of interest, other mode frequencies need not be determined.

  Since parts such as gear 12 have not yet been assembled into the transmission when tested, step 50 utilizes a gear that has the same design and format as gear 12 and is processed and manufactured in the same manner as gear 12. Determining a mode frequency of the transmission to perform. In this way, the form and extent of gear failures that occur in the gear inspection device 10 and the transmission, respectively, will be similar.

  The fundamental frequency and other mode frequencies of a transmission, such as transmission 46, can be determined by any method effective to provide the desired result. For example, a vibration sensor, such as an accelerometer, can be placed on the transmission housing at the same location as the vibration sensor used for the line end test bench. Such a sensor is of the same type as used on the inspection device 10 and, if convenient, one of the sensors 40, 41 can be removed from the inspection device and used on the transmission. .

  The sensor is coupled to a data collection and output device, such as a computer. Thereafter, the transmission housing is struck with an impact device hammer. The hammer can be provided with a sensor for measuring the impact force. Transmission vibration response data is transformed using a fast Fourier transform well known in the art and plotted in the frequency domain as shown in FIG. The illustrated graph shows some of the structural mode frequencies of the transmission being tested, including a fundamental frequency of approximately 1760 hertz (Hz).

  In addition to the fundamental frequency and other mode frequencies of the assembly, such as transmission 46, at least one abnormal frequency of components operating in the assembly is also determined (see step 52 in FIG. 3). It is the abnormal frequency of the part that operates in the assembly, but for convenience it is called the assembly abnormal frequency. When the vehicle transmission is an assembly, one anomalous frequency of interest is the gear meshing frequency, ie the transmission gear meshing frequency. The “transmission” modifier indicates that it is the gear meshing frequency of the gear when it operates in the assembled transmission. Other assemblies may use differently named abnormal frequencies.

  In general, an abnormal frequency is an operating frequency at which a component abnormality is detected when the component is operating in an assembly. For example, in the case of a vehicle transmission, such as transmission 46, it is known that a gear tooth anomaly can create undesirable noise and vibration as it rotates. For example, when other assemblies, such as crankshafts in an engine, or preliminary assemblies are analyzed, the anomalous frequency is not the gear meshing frequency and an anomaly in the component being analyzed is desirable in the assembly. There may be several other frequencies that produce no noise or vibration. Thus, the present invention can be used in any assembly that includes moving parts and where abnormalities in the parts generate undesirable noise or vibrations at known frequencies or groups of frequencies.

  In the case of the gear 12 in the transmission 46, the abnormal frequency is, for example, the transmission gear meshing frequency, which is a function of the number of teeth on the gear 12 and the rotational speed in the transmission 46. For example, if gear 12 has 57 teeth and rotates in transmission 46 at a speed of 875 revolutions per minute (875 RPM), transmission gear mesh frequency (T-GMF) Is easily calculated from the following formula: T-GMF = (857PM) x (57) / (60 seconds / min). Therefore, in the above example, the transmission gear meshing frequency is 831.25 Hz.

  The transmission gear mesh frequency is then compared with the fundamental frequency and other mode frequencies of the transmission 46 as shown in FIG. FIG. 4 shows a predetermined frequency band (band 1) of the transmission 46. The predetermined frequency band of the transmission includes the mode frequency as plotted in FIG.

  Referring to FIG. 3, in step 54, the harmonic frequency of the transmission gear meshing frequency, i.e., an integer multiple of the transmission gear meshing frequency, is determined, and the correlation with the mode frequency of the fully assembled transmission is determined. The positional relationship (the positional relationship on the horizontal axis of the graph as shown in FIG. 4) is examined. We are interested in whether the transmission gear meshing frequency or its harmonic frequency is close to one of the transmission mode frequencies, for example, within 20%. As described above, the transmission gear meshing frequency is 831.25 Hz, and when this value is compared with the graph shown in FIG. 4, the transmission gear meshing frequency of 831.25 Hz is in any mode frequency of the transmission within the predetermined frequency band. It is understood that it is not within 20%.

  Thereafter, the harmonic frequency of the transmission gear meshing frequency is calculated to determine whether any harmonic frequency is close to any mode frequency of the transmission within the predetermined frequency band. The second harmonic frequency of the transmission gear meshing frequency is (831.25 Hz) × 2 = 1662.5 Hz, so the second harmonic frequency of the transmission gear meshing frequency is 20 of the primary structural mode frequency of the transmission. Within%.

  It should be noted here that other tolerances of 20% can be used to determine whether the abnormal frequency is close to the mode frequency of the assembly. For example, based on experimentally obtained data or other methods, the allowable frequency band may be selected as a percentage of mode frequency, for example, plus or minus 10%, plus or minus 5%, for example .

  In step 56 shown in FIG. 3, the amplitude response of the assembly is measured using both bad and accepted parts in the assembly. For example, for transmission 46, first the amplitude response is measured when it includes a gear with at least one known defect, and then the transmission 46 is substantially defect-free, i.e. undesirable NVH characteristics in the gear. Amplitude response is measured when including a non-defective gear. The amplitude response is measured using the same sensor that is used to determine the mode frequency of the transmission 46. The identifier (abnormal identification parameter) of the gear 12 in the transmission is then determined by comparing the two amplitude responses. For example, the identifier can be determined by utilizing the deviation of the two amplitude responses, or the ratio of the two. This identifier is used as much as possible to help adjust the inspection apparatus 10.

  In step 58, a target speed range for operation of the inspection device is selected, which is higher than a conventional low speed gear inspection device suitable for vibration detection. Various factors can be considered to determine the desired operating speed, such as, for example, whether the gear 12 is being refueled throughout the test. The inspection device 10 is configured to rotate the gear 12 without being lubricated. Therefore, it is necessary to rotate the gear 12 at a sufficiently low speed compared to the speed at which the gear 12 rotates in the transmission.

  If the rotational speed of the gear 12 in the inspection apparatus 10 is selected, the inspection apparatus abnormal frequency, that is, the inspection apparatus gear meshing frequency is determined by knowing the number of teeth of the gear 12 (see step 60). As with the assembly abnormal frequency, the inspection apparatus abnormal frequency has the modifier “inspection apparatus”, but it will be understood that this is the abnormal frequency of the part operating in the inspection apparatus. Then, the harmonic frequency of the inspection device gear meshing frequency is determined (see step 62 in FIG. 3).

  The inspection device abnormal frequency is a function of the number of teeth of the gear 12 and the rotational speed, similarly to the transmission gear meshing frequency. If the inspection device 10 is configured to rotate the gear 12 at 120 RPM, the inspection device gear meshing frequency can be easily calculated as 114 Hz, so the second harmonic frequency of the inspection device gear meshing frequency is 228 Hz. It is. It is the second harmonic frequency (1662.5Hz) of the transmission gear meshing frequency that is within 20% of the basic frequency of the transmission 48. Therefore, what is important in the structural adjustment of the gear inspection device is the gear of the inspection device. The second harmonic frequency (228 Hz) of the meshing frequency.

  As shown in FIG. 3, in step 64, the inspection device 10 is designed and manufactured (configured) to operate the gear 12 at the desired test conditions. Further, in step 66, the gear inspection device is constituted by a structural component optimized for detection of gear abnormality. For example, at least a part of the inspection apparatus 10 is configured to have at least one mode frequency within a predetermined frequency band of the inspection apparatus 10. The predetermined frequency band of the inspection device is the inspection device gear meshing frequency and its harmonic frequency (since the second harmonic frequency of the transmission gear meshing frequency is within 20% of the transmission mode frequency, at least the second harmonic frequency. )including. Of course, for other components, other abnormal frequencies and / or harmonic frequencies of other abnormal frequencies may be of interest.

  The inspection device 10 may also at least partially include, for example, mode frequency and mode amplitude, such that the identifier value of the inspection device 10 falls within a predetermined range determined based on the identifier value of the transmission 46. It is configured to have proper mode characteristics. For example, if the value of the identifier of the transmission 46 using the defective gear and the acceptable gear is 3: 1, the predetermined range of the value of the identifier of the inspection device 10 may be 2.5: 1 to 3.5: 1. . Of course, a narrower band may be used that requires that the value of the identifier of the inspection device be adjusted closer to that of the assembly for a given range.

  The identifier of the inspection device 10, i.e., the relative amplitude response difference between the bad gear and the acceptable gear, is determined using the same sensor used to determine the mode frequency of the inspection device. Appropriate adjustment of the inspection apparatus 10 may require several iterations until the desired mode characteristics are obtained. Once the desired mode characteristics of the inspection device 10 are obtained, the design / configuration is complete and the inspection device 10 can be used with components such as the gear 12.

  Similar to the graph of the structural mode (frequency characteristics) of the transmission 46 shown in FIG. 4, the structural mode of the inspection apparatus 10 is determined using the impact hammer and sensor described above. FIG. 5 shows the structural mode of an inspection device such as inspection device 10. The mode frequency is plotted over the mode frequency band (band 2) of the inspection device. At the design stage, structural analysis techniques well known in the art, such as the vocabulary element method, can be used to estimate the mode frequency of the inspection device.

  In order to adjust the fundamental frequency of the inspection device 10 or to structurally adjust the inspection device 10, the structure of the various components can be modified or individually adjusted. For example, the spindle 21 can be made longer or shorter as required. It is also possible to place an inertia disk on the surface of the parent gear 24 in order to increase the mass of the inspection device 10. Similarly, other components of the gear inspection device 10, such as the spindle 26, can be made larger or smaller as required. Although the inspection device 10 includes many different components, the fundamental frequency and other mode frequencies of the inspection device 10 are limited to only a portion of the gear inspection device 10, for example, components on the base 31, particularly the spindle housing and , Affected by the rotating elements of the two spindles 21, 26 with respect to the test gear and the parent gear.

  As shown in FIG. 3, in step 68, the gear 12 is rotated by the motor 14 and the vibration of the gear inspection device 10 is measured by the sensors 40, 41 (see step 70). FIG. 6 (a) shows a graph of data measured by a sensor such as sensor 40 on gear inspection device 10. In the ordinate, the amplitude of the measured acceleration is given in terms of gravitational acceleration (G's). As shown in the figure, the acceleration value is measured over a predetermined time. The data shown in the figure is collected from the operation of a gear such as gear 12 having a known gear profile defect. For comparison purposes, FIG. 5 (b) shows a similar output for vibration acceleration measured on a master gear spindle, such as spindle 26. FIG.

  In order to make it easy to distinguish in the time domain when operating a gear having a defect and when operating a gear without a defect, graphs of time domains shown in FIGS. 6 (a) and 6 (b), respectively. (Time domain plot) can be converted into a frequency domain plot as shown in FIGS. 7 (a) and 7 (b), respectively. Such a transformation can be achieved by the use of a fast Fourier transform or some other mathematical algorithm known in the art. In the frequency domain, the gear failure frequency, i.e., the gear meshing frequency and its harmonic frequency, are identified and when the gear inspection device is operated with a gear without defects and when operated with a gear with defects. The level seen is identified. As described above, the structure of the inspection apparatus is adjusted so that it is easy to distinguish when operating with a gear having no fault at the gear fault frequency and when operating with a faulty gear. Therefore, converting the measured time domain output to the frequency domain identifies the excitation due to gear faults, and detection of faults in the gear between the passing gear and the bad gear at those frequencies. Provide a more appropriate identifier that further promotes

  In particular, after actuation by the test gear, the vibration output from the inspection device 10 recorded digitally can be compared with one predetermined amplitude value or a value given in the form of a template. Such a template can be placed on an output graph as shown in FIGS. In addition, various parameters of the gear inspection device 10 can be modified to make it easier to distinguish between good and bad parts. For example, in the case of gears 12 and 24 meshing within the inspection device 10, the guide portion 28 can be adjusted to change the backlash between the gears 12 and 24 meshing. Depending on the specific setting of the inspection apparatus 10, a certain backlash value may give a large discriminating power between a gear having a defect and a gear having no defect. This type of data can be collected experimentally using gears with known characteristics.

  In general, the method described in FIG. 3 can be used to perform function-based inspections on different types of rotating or sliding parts before being used in their assemblies. As another example, the camshaft is an important part in the engine and chatter on the camshaft is a major NVH concern related to customer satisfaction. The rattling noise of the camshaft is heard as an unpleasant noise in the engine due to unevenness (undulations) on its surface. Although the camshaft is sharpened and polished and inspected in some sizing instruments, the problem of camshaft noise remains in the engine. The surface finish measuring device installed in the factory measures the rattling noise according to the manufacturing specifications, but the chatter noise on the camshaft is not excited in the engine due to its structural characteristics. . Therefore, it is still difficult to distinguish between an acceptable camshaft and a defective camshaft in relation to the NVH level generated when assembled in the engine and rotating at high speed. The method of the present invention can be used to inspect the camshaft for chatter that can cause undesirable NVH levels in the assembled engine, similar to that described for transmissions and gears.

  Having described in detail the best mode for carrying out the invention, those skilled in the art to which the invention pertains will present various alternative designs and alternatives for carrying out the invention as defined in the claims. Embodiments will be recognized.

It is a top view of the components inspection apparatus according to this invention. It is the schematic which compares the action | operation of a transmission with the test | inspection apparatus shown in FIG. 1 regarding the structural excitation resulting from a component defect. 4 is a flowchart illustrating a method according to the present invention. It is a graph of the structural mode of the transmission housing | casing of a vehicle provided with all the assembled parts. It is a graph of the structural mode of component inspection apparatuses like the component inspection apparatus shown in FIG. 2 is a graph of vibration acceleration values measured for a predetermined time from a structurally adjusted component inspection device such as the component inspection device shown in FIG. 1. It is the graph which converted the graph of FIG. 6 into the frequency domain.

Claims (21)

A method for detecting an abnormality in a part that is movable at one or more speeds in an assembly prior to the part being installed in the assembly,
Comprising a component inspection device comprising at least one inspection device sensor and capable of operating the component at one or more predetermined speeds;
Selecting from one or more predetermined speeds to determine the operating speed of the components in the inspection device;
Determining at least one inspection device abnormal frequency that is a function of the operating speed of the component in the inspection device;
Configuring at least a part of the inspection device to have at least one mode frequency within a predetermined frequency band including at least one of the inspection device abnormal frequencies of the component;
In the assembly or inspection apparatus, the abnormality identification parameter is determined so as to be obtained by comparing the amplitude responses of the case where at least one part having abnormality is used and the case where a part having no abnormality is used. Once defined, at least a part of the inspection apparatus is set to at least one part so that a value of the identification parameter relating to a part in the inspection apparatus is within a predetermined range with respect to a value of the identification parameter relating to the part in the assembly. Configuring to have mode characteristics determined using two inspection device sensors;
Operating the component in the inspection device;
Measuring a value of a predetermined response parameter of the inspection device while the component is operating in the inspection device, thereby facilitating detection of abnormality of the component;
A method for inspecting a part. Determining at least one mode frequency of the assembly using at least one assembly sensor;
Determining at least one assembly anomaly frequency that is a function of the operating speed of the component in the assembly and at which at least one anomaly can be detected when the component operates in the assembly;
Determining whether at least one abnormal frequency of a component in the assembly is within a predetermined frequency band including at least one of the mode frequencies of the assembly;
Determining a mutual positional relationship between the at least one abnormal frequency and the at least one mode frequency of the assembly;
The method of claim 1, further comprising: In a state where the assembly includes at least one part having an abnormality, a step of using at least one assembly sensor to obtain a first amplitude response which is an amplitude response of the assembly, and the assembly has no abnormality. Using at least one assembly sensor to determine a second amplitude response that is an amplitude response of the assembly, including the component, and
The method of claim 2, wherein the first amplitude response and the second amplitude response are compared when determining the value of an identification parameter for a part in the assembly.   2. The method of claim 1, wherein the measured amplitude response of the inspection device measured while the part is in operation is compared with a predetermined value, thereby further facilitating detection of an abnormality of the part.   The method of claim 1, wherein the predetermined response parameter of the inspection device is vibration, and a value of the vibration is measured using the at least one sensor. To measure the vibration, measure at least one of acceleration, velocity, displacement and acoustic properties,
The method according to claim 5, wherein the measurement is performed over a bandwidth including the predetermined frequency band of the inspection apparatus. Further comprising converting at least some measurements from the time domain to the frequency domain;
6. The method of claim 5, wherein the converted value is compared to a predetermined value, thereby further facilitating detection of the component abnormality. Further comprising the step of engaging the part in the inspection device by means of a meshing part;
The method of claim 1, wherein the engagement and engagement component in the inspection device corresponds to the engagement and engagement component of the component in the assembly. A method for detecting an abnormality in a particular gear for a vehicle transmission prior to the gear being installed in the transmission,
Determining at least one mode frequency of the transmission using at least one sensor on the transmission housing; and
Determining a transmission gear mesh frequency as a function of the number of teeth of the specific gear and the rotational speed of the specific gear within the transmission;
Determining whether the transmission gear meshing frequency is within a predetermined transmission frequency band including the at least one mode frequency of the transmission;
Determining a mutual positional relationship between at least one mode frequency of the transmission and the transmission gear meshing frequency;
Determining whether at least one of the harmonic frequencies of the transmission gear meshing frequency is within the predetermined transmission frequency band;
Determining a mutual positional relationship between the at least one mode frequency of the transmission and at least one harmonic frequency of the transmission gear meshing frequency;
Using at least one sensor on the transmission housing to determine a first amplitude response that is an amplitude response of the transmission including a gear having at least one anomaly;
Using at least one sensor on the transmission housing to determine a second amplitude response that is an amplitude response of the transmission including a gear having substantially no abnormality;
Determining an anomaly identification parameter for the particular gear in the transmission by comparing the first amplitude response and the second amplitude response;
Comprising an inspection device including at least one sensor and capable of rotating the specific gear at at least one or more predetermined speeds;
Selecting from the one or more predetermined speeds to determine a rotational speed for the particular gear in the inspection device;
Determining an inspection device gear meshing frequency as a function of the number of teeth of the specific gear and the rotational speed of the specific gear within the transmission;
Determining at least one of the harmonic frequencies of the inspection device gear meshing frequency;
At least one mode frequency of at least a part of the inspection device falls within a predetermined frequency band of the inspection device, wherein at least one of the mode frequencies includes at least one of the inspection device gear meshing frequency and the harmonic frequency of the inspection device gear meshing frequency. A step of configuring
Abnormality related to the specific gear in the inspection device, which is obtained by comparing the amplitude response of the inspection device between the case where a component having at least one abnormality is used and the case where a component having no abnormality is used At least a part of the inspection device is determined using the at least one sensor so that the value of the identification parameter is within a predetermined range with respect to the value of the abnormality identification parameter relating to the specific gear in the transmission. Further configuring to have mode characteristics;
Rotating the specific gear in the inspection device;
Measuring a value of a predetermined response parameter of the inspection device while the specific gear is being rotated in the inspection device, thereby facilitating detection of an abnormality in the gear;
A transmission gear inspection method comprising:   The method of claim 9, further comprising applying a torque load to the specific gear while the specific gear is rotating in the gear inspection device.   11. The method according to claim 10, further comprising a step of configuring the inspection device with a meshing gear for meshing with the specific gear, wherein the torque load is applied to the specific gear via the meshing gear. The method described.   The method of claim 11, wherein the particular gear and the meshing gear are engaged with each other by a single side contact.   12. The method of claim 11, wherein the specific gear drives the meshing gear, and the specific gear is rotated at a speed that is less than the speed used to determine the transmission gear meshing frequency. .   The method according to claim 9, wherein the predetermined response parameter is vibration, and the measured value is a value of acceleration in at least a part of the inspection device measured by the at least one sensor over a predetermined time. Converting at least a portion of the measured value from the time domain to the frequency domain;
15. The method of claim 14, comprising comparing at least one of the converted values with a predetermined value, thereby facilitating detection of the specific gear abnormality. An inspection device based on vibration characteristics adjusted by the structure for detecting an abnormality of a movable part in an assembly having a mode frequency before the part is mounted in the assembly. There,
For the movable part, at least one assembly abnormality having a frequency at which an abnormality can be detected, a function of the operating speed within the assembly, at least one being within a predetermined frequency band of the assembly At least one inspection device abnormal frequency, each of which is a function of a frequency and an operating speed in the inspection device, at least one of which is different from at least one of the assembly abnormal frequencies,
A first actuator capable of operating the movable part at one or more predetermined speeds;
At least a portion is configured to have at least one mode frequency within a predetermined frequency band including the at least one inspection apparatus abnormal frequency, and the movable part is operated while the movable part is operated by the first actuator. A structure that supports the component;
A sensor for measuring a value of a predetermined response parameter while the first actuator operates the movable part;
Inspection apparatus for parts having   The apparatus of claim 16, further comprising a second actuator capable of loading the movable part while the first actuator is actuating the movable part.   18. The apparatus according to claim 17, further comprising a second part configured to cooperate with the second actuator and the movable part, wherein the second actuator applies a load to the movable part via the second part. apparatus.   The movable part is a gear of a vehicle transmission, the first actuator can rotate the gear, and the second actuator can apply a torque load via a meshing gear that contacts the gear. The apparatus of claim 18.   The apparatus of claim 19, wherein the transmission gear and the meshing gear engage each other by a single side contact.   The apparatus of claim 16, wherein the predetermined response parameter is vibration and the sensor measures an acceleration value.

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